Hi there, I think any kind of skeptical material will help open your mind, even coming from a polytheistic background.
I didn’t find reason by searching specifically for ‘skepticism’ or ‘atheism’, I found it in a very gentle way by watching a series of lectures by Richard Dawkins which were about evolution.
As a scientifically inclined skeptic (instead of woo – though will still be active in terms of this), I found Carl Sagan’s Cosmos important in opening my mind and forming my opinion. There is a lot of great stuff on the internet to be found – free stuff!!
Peruse and discover at your own leisure.